Devices including sensors such as an acceleration sensor, an angular velocity sensor, and a photosensor, etc., are widely used. For example, a mobile communication terminal such as a smartphone or a tablet, which is equipped with a built-in acceleration sensor, can recognize a three-dimensional gesture of a user registered in advance, and execute an instruction according to the recognized gesture.
Furthermore, there is known a system for providing intuitive playing activities, by recognizing a gesture of a user through a remote controller of a video game console equipped with a built-in acceleration sensor, and associating the recognized gesture with a gesture of a character in the video game (Patent Literature 1, Patent Literature 2).
Furthermore, there is known a technology of recognizing a physical behavior (beating, stroking, etc.) of a user with respect to a robot for reproducing contents, and reproducing contents according to the recognized gesture (Patent Literature 3), and a technology of controlling a device by combining voice sounds and gestures (Patent Literature 4).
As a method for determining whether a physical gesture of a user described above matches a gesture registered in advance, for example, there is known an algorithm referred to as Dynamic Time-Warping (Non-patent Literature 1, Non-patent Literature 2).